Cardiovascular disease has the highest mortality in the US, causing one million heart attack and stroke deaths each year. More and more studies have reported that it is total homocysteine (tHCY) that plays a critical role in heart disease and stroke, as well as numerous other diseases. Hyperhomocysteinemia is a major risk factor of death of cardiovascular disease in patients with end-stage renal disease (ESRD) and plasma tHCY may be used as a new tumor marker to monitor cancer patients during chemotherapy. It has been reported that Alzheimer's disease patients and individuals with diabetes may have significant elevated plasma tHCY. In other diseases such as Parkinson's disease, homocysteine may play a role in sensitizing dopaminergic neurons to dysfunction and death. The concentration of tHCY may also be associated with common pregnancy complications and adverse pregnancy outcomes. Measuring tHCY levels routinely may assist physicians over the course of the pregnancy in monitoring the health of the fetus and the mother.
Various methods have been developed for measuring total homocysteine (tHCY) in plasma. These various methods include tHCY enzyme conversion immunology assays designed for the Abbott IMx analyzer, a microtiter plate tHCY enzymatic immunoassay, high performance liquid chromotography (HPLC) methods assays using multiple enzymes, and gas chromatography-mass spectrometry methods. These methods however, are complex, require highly specialized equipment to perform and have limited throughput. While a simpler four-reagent single-enzyme assay has been developed that does not require the specialized equipment of previous methods, the four-reagent assay is still more complicated than the assay disclosed herein. The four reagent assay includes additional reagents and steps in order to measure tHCY. The four reagent method is more expensive, requires more time to provide accurate readings, and is not applicable to most automated robotic analyzers currently in use. Thus there is a need for a tHCY assay that can measure the amount of tHCY that is simpler, cheaper, faster, and easier to perform than previous methods.